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1.
记述了新疆玛纳斯古近纪安集海河组发现的鲤科(Cyprinidae)一新属、种——刘氏天山鱼(Tianshanicus liui gen.et sp.nov.)。新属具有臀鳍分叉鳍条多于7根、体长形稍侧扁、口端位、下咽齿近锥形而齿尖前后略侧扁、背鳍和臀鳍均无硬棘、背鳍起点略在腹鳍起点之后以及尾鳍深分叉等特征,表明它应属于雅罗鱼亚科(Leuciscinae sensu Cavender & Coburn,1992)。然而,它又具有额骨前宽后窄、顶骨长方形、膜质蝶耳骨很大、齿骨冠状突较低、鳃盖骨近长方形等特征而有别于本亚科中其他属。值得注意的是,这些特征却见诸于现生的胭脂鱼类Myxocyprinus中,这将对研究雅罗鱼类的起源很有意义。根据鱼化石和哺乳化石的证据,认为含鱼层的时代为晚始新世。  相似文献   

2.
记述了辽宁阜新县大五家子镇三吉窝铺的鱼化石。该鱼具有颞孔 ,前上颌骨小 ,上颌骨大 ,辅上颌骨 1块 ,口缘有一行锥形齿 ,背鳍小于臀鳍 ,1 6根分叉尾鳍条 ,尾下骨 7块 ,尾上骨 1块 ,尾神经骨 3~ 4块。这些特征基本上是狼鳍鱼的定义特征 ,因此 ,应该属于狼鳍鱼属。阜新标本的第三眶下骨呈半圆形 ,不同于狼鳍鱼属各已知种。阜新标本的下颌长而低 ,在狼鳍鱼属中 ,只有三棵榆树狼鳍鱼和德永氏狼鳍鱼的下颌与之相似。但阜新的标本在具有 1 0根胸鳍主要鳍条、1 6根尾鳍分叉鳍条以及 1块尾上骨方面不同于三棵榆树狼鳍鱼。与德永氏狼鳍鱼相比 ,阜新标本的第三眶下骨小、半圆形、后端不伸达前鳃盖骨的前缘 ,辅上颌骨较大 ,身体较宽。根据上述阜新标本的特征 ,建立狼鳍鱼属一新种———阜新狼鳍鱼。  相似文献   

3.
王丹  赵亚辉  张春光 《动物学报》2005,51(3):431-439
海鲇属Arius鱼类是世界上重要的海洋捕捞对象之一。长期以来,国内有关研究者将分布于我国海域的腭骨齿单侧一群的海鲇属个体定名为中华海鲇A·sinensis。据查证,原TachysurussinensisLac啨p埁de,1803的命名仅依据一幅中国画,不具科学上的有效性。而Valenciennes在1840年记录的新种A·sinensis背鳍无棘,臀鳍鳍条数13,与我国被定名为“中华海鲇”的标本(背鳍有棘,臀鳍鳍条数16-19)的特征不符。基于中国科学院动物研究所标本馆馆藏标本的研究认为,A·sinensis的科学名无效,我国原被定名为“中华海鲇A·sinensis”的标本实际应为丝鳍海鲇A·arius(Hamilton,1822)。进一步分析显示,丝鳍海鲇雌雄个体间存在显著的形态差异:雌性个体与雄性个体相比腭骨齿群面积较大,两侧齿群间距较小(0·2%vs0·4%,体长),腹鳍较长(17·7%vs14·4%,体长),眼后头长较小(12·3%vs14·7%,体长)[动物学报51(3):431-439,2005]。  相似文献   

4.
2010年3月下旬-7月上旬于浙江富阳市农田采集680只泽陆蛙(Fejervarya limnocharis),研究了泽陆蛙成体和幼体的个体大小和局部形态特征的两性异形;通过解剖雌体获得窝卵数、测量抱对个体获得形态数据,研究了雌体大小与生育力关系以及抱对两性个体体形大小的相关性.结果表明:捕获个体中,雌性和雄性成体的最小体长分别为33mm和30 mm;雄性成体个体数显著超过雌性成体,两性幼体个体数无显著差异;两性成体头部大小、四肢长随体长呈同速增长,眼径和体重随体长呈异速增长,两性幼体所有被检形态特征均随体长呈同速增长;雌性成体平均体长显著大干雄性成体,去除体长差异的影响后发现,除眼径无显著的两性差异外,其余被检形态特征均为雌性大于雄性;幼体除雌性体重大于雄性外,其余被检形态特征均无两性差异;窝卵数与雌体大小(体长和体重)呈显著的正相关;两性抱对个体的体长无显著相关性;泽陆蛙雄性成体体形小于雌性成体的个体大小两性异形模式可能决定于驱使雄性向较大体形发展的进化驱动力相对较弱,雌性增大体形可增加繁殖输出,故向较大体形发展的进化驱动力相对较强;除体重外,其余被检形态特征的两性异形均形成于性成熟之后.  相似文献   

5.
记述了辽宁西部九佛堂组和义县组中华弓鳍鱼一新种:辽宁中华弓鳍鱼Sinamia liaoningensis,并与该属的其他种进行了比较.新材料具有中华弓鳍鱼科的3个定义特征:单一的顶骨,三对额外肩胛骨和膜质翼耳骨短并与顶骨等长,无疑应归入该科.新种的后眶下骨较小,背鳍长大,鳞片菱形,因此,归入中华弓鳍鱼属.辽宁中华弓鳍鱼在以下几个方面不同于中华弓鳍鱼的5个已知种:体型短粗,吻骨较短,鼻骨近四方形,围眶骨较多(6),前鳃盖骨强烈弯曲,背鳍条较少(18),尾鳍条较多(16),臀鳍鳍基起点到鱼体背缘的鳞列较多(32),鳞片后缘不具锯齿,尾鳍具有纤维状的角质鳍条.  相似文献   

6.
以黄海捕捞的丝背细鳞鲀(Stephanolepis cirrhifer)为实验样本,共100尾,体全长7.00~14.50 cm,体重7.96~136.54 g。对其外部形态进行观察绘图描述,分析其鱼体侧面和头部、第二背鳍鳍条和鳞片的形态特征。对可量性状与可数性状进行测量和线性回归分析。对背鳍鳍条、尾鳍鳍条、臀鳍鳍条和胸鳍鳍条数量进行统计。观察发现,(1)体表被形态多样的绒状鳞片,鳞片为形似盾鳞的骨鳞,由基板和骨质凸起组成;腹鳍棘与腹部之间具有一可收缩的皮质三角形结构,体表布满黑色条纹与黑色斑点,以眼部为中心向外延伸出6条主侧线(背侧线、框上线、框下线、前鳃盖线、下颌线、上颞线)为其外部形态的明显特征。(2)线性相关性最好的是全长(TL)/体长(SL),其比值变动范围最小,雌雄差异小,相关方程为:SL=0.8239TL﹣0.0471(R2=0.9763);线性相关性最差的是头长/吻长,其比值不仅变动最大,而且雌雄的差异最大。(3)体长(SL)与体重(W)的关系为:W=2.3743e0.2803SL(R2=0.96);雄性:W=2.5406e0.2737SL(R2=0.96),雌性:W=2.0328e0.2954SL(R2=0.95)。(4)鱼鳍鳍条数量:第一背鳍为两根背鳍棘,第二背鳍30~34;臀鳍29~34;胸鳍12;尾鳍13;腹鳍为一个腹鳍棘。雌雄第二背鳍的第二根鳍条长度存在差异,雄性长度比雌性长约1/6~1/5。丝背细鳞鲀在黄海的出现,说明该鱼种洄游分布范围已经扩大到黄海。  相似文献   

7.
中国犁齿鲷属鱼类一新种(鲈形目,鲷科)   总被引:3,自引:0,他引:3  
记述了采自闽南-台湾浅滩渔场的鲷科鱼类1新种,单长棘犁齿鲷Evynnis mononematos sp.nov.。新种的犁骨有数颗圆锥状小齿,为犁齿鲷属所特有的特征。其背鳍仅第3鳍棘末端呈显著的丝状延长这一特征可与本属已知种E.cardinalis和E.tumifrons相区别。  相似文献   

8.
2003年4月,于怒江二级支流镇康县境内的大叉河中采获一批墨头鱼属(Garra)鱼类标本,经鉴定为一新种,命名为怒江墨头鱼(G. nujiangensis Chen and Yang, sp. nov.)。该新种主要鉴别特征:围尾柄鳞12~14;侧线鳞48~50;在小个体中有一对微小的吻须;背鳍分支鳍条 8~9;侧线上鳞5~6,侧线下鳞3~4;体高小于头长;臀鳍起点处的小于眼后至吻端的距离;腹鳍前长为体长的50.0%~53.7%;肛门前长为体长的58.9%~63.9%;体宽为体长的 16.7%~19.6%;体高为体长的19.2%~22.6%。本研究证实,在缺须的墨头鱼属的一些物种中,如高体墨头鱼(G. alticorpora)和怒江墨头鱼(G. nujiangensis),其幼体中往往具有一对很小的吻须。  相似文献   

9.
记述了弓鳍鱼亚科一新种:Cyclurus orientalis(东方圆尾鱼),标本采集于中国湖南省湘乡市下湾铺早始新世至中始新世下湾铺组。化石因具有以下特征而被归入弓鳍鱼亚科(Ami-inae):尾前椎为双椎型;除第一尾椎和第一尾下骨外,其余尾椎和尾下骨均一对一愈合;无膜质尾骨;背鳍长。因其第一冠状骨上的牙齿顶端圆钝,而被归入Cyclurus属。本新种与Cy-clurus属中其他种的区别在于:背鳍鳍条较少;身体短而高;脊椎和椎体较少。在始新世淡水鱼类的跨太平洋分布达到鼎盛时,由于弓鳍鱼亚科并非仅分布于太平洋两岸的类群,因此不能作为跨太平洋分布的指示类群。弓鳍鱼亚科在北半球的分布范围更广,与某些其他淡水鱼类群例如狗鱼科(Esocidae)和骨舌鱼科(Osteoglossidae)相似,这种现象只能用有别于形成跨太平洋分布的地质背景来解释。  相似文献   

10.
记述了在江苏句容发现的中华鳞齿鱼属(Sinolepidotus)一新种——长背鳍中华鳞齿鱼(Sinolepidotus longidorsalis sp.nov)。新种的一般形态特征如身体高纺锤形,背鳍长,臀鳍离尾鳍近,头骨外部骨片的形状及排列格局,口裂小,下颌骨有较高的冠状突,口缘牙齿高而尖,体侧中部和背区的一些鳞片高显著大于宽等,与浙江早白垩世的浙江中华鳞齿鱼(Sinolepidotus chekiangensis)很相似。但新种具有背鳍较长,背鳍鳍条数目较多,吻突尖,及鳞片后缘梳状齿不发育等特征区别于浙江中华鳞齿鱼。此外,评论了中华鳞齿鱼属的系统位置,认为它的形态特征与Paralepidotus很相似,对它原列入半椎鱼科提出疑问。根据长背鳍中华鳞齿鱼的性质并参考有关地质古生物资料,将含鱼层杨冲组的时代定为早白垩世。  相似文献   

11.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

13.
14.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

15.
16.
Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

17.
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

18.
19.
Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

20.
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

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